1. Field of the Invention
The present invention relates to a magnetic recording reproducing apparatus and, more specifically, to a magnetic recording reproducing apparatus carrying out recording/reproducing by drawing a magnetic tape wound around a reel.
2. Description of the Background Art
FIG. 21 is a plan view of a slide chassis of a conventional magnetic recording reproducing apparatus. The magnetic recording reproducing apparatus is used in a camcorder, that is, a small portable video tape recorder and camera or the like.
Loading arms 3a and 3b are attached on a rear side of a slide chassis 1 rotatable around rotation shafts 5a and 5b, respectively. Parts such as linking arms, guide base and so on connected to the loading arms are not shown.
Slide chassis 1 includes slide chassis guiding grooves 43a, 43b, 43c and 43d. Guide pins provided on a main chassis 51, which will be described later, are fitted in slide chassis guiding grooves 43a, 43b, 43c and 43d, which allow slide chassis 1 to slide in the directions of the arrows A and B. A spring hook 41 is fixed on slide chassis 1.
FIG. 22 is a plan view of a main chassis of a conventional magnetic recording reproducing apparatus.
On main chassis 51, a loading motor 93, mid gears 96a-96e and a main cam 53 are rotatably provided. The reference numeral 55 denotes a rotation shaft of main cam 53. Driving force of loading motor 93 is transmitted through mid gears 96a-96e to main cam 53.
On main chassis 51, a lever 59 for driving the slide chassis is provided rotatable about a rotation shaft 61. A lever 59 for driving the slide chassis is arranged on main cam 53, and a cam pin 63 provided at lever 59 for driving the slide chassis is fitted in a groove 57 for driving the slide chassis provided at main cam 53.
A pin 65 for driving the slide chassis provided at the lever 59 for driving the slide chassis is fitted in a groove portion 56 provided the spring hook 41 on slide chassis 1 (see FIG. 21). By the rotation of main cam 53, cam pin 63 drives lever 59 for driving the slide chassis in the directions of the arrows C and D, so that slide chassis 1 slides in the directions of the arrows A and B (see FIG. 21).
A loading lever 101 is arranged on main chassis 51. By fitting a guide pin 52 on main chassis 51 in a loading lever guiding groove 50 provided at loading lever 101, loading lever 101 is made slidable in the directions of the arrows A and B. A cam pin 66 provided at loading lever 101 is fitted in a groove 60 for driving the loading lever provided at main cam 53. Namely, by the rotation of main cam 53, loading lever 101 slides in the directions of the arrows A and B.
A lever 71 for bringing a pinch roller into tight contact is rotatably attached on main chassis 51. The pinch roller is driven by utilizing the rotation of the lever 71 for bringing the pinch into tight contact. A cam 70 for bringing the pinch roller into tight contact, and mid gears 78a and 78b are provided rotatable on main chassis 51. Rotation of main cam 53 is transmitted through mid gears 78b, 78a and the cam 70 to the lever 71, and hence the lever 71 rotates. In the figure, the reference numeral 77 denotes a drum. By rotating the loading arms 3a and 3b, a guide roller (not shown) connected to loading arms 3a and 3b takes up a magnetic tape (not shown), bring the tape into tight contact with the drum 77, and allows recording/reproducing on the magnetic tape. The operation of rotation of the loading arms 3a and 3b in a conventional magnetic recording apparatus will be described with reference to FIGS. 23-25.
FIG. 23 shows a state of ejection. In the state of ejection, end portions 92a and 92b (see FIG. 21) of loading arms 3a and 3b are in contact with loading arm bending portions 107a and 107b provided at the loading lever 101, so that loading lever 101 is bent inward. Since end portions 92a and 92b are formed of resilient material, there is generated a force to stretch, so that forces in the directions of H and I are applied to loading arms 3a and 3b, respectively.
When loading motor 93 rotates at this state, lever 59 for driving the slide chassis begins to rotate in the direction of the arrow D. Thus, slide chassis 1 moves in the direction of the arrow B.
When slide chassis 1 further slides in the direction of the arrow B, end portions 92a and 92b are separated from loading lever bending portions 107a and 107b, and thereafter, loading arm depressed portions 109a and 109b (see FIG. 21) provided at loading arms 3a and 3b engage with loading lever pins 111a and 111b provided at loading lever 101, and thus sliding of slide chassis 1 is completed as shown in FIG. 24.
After the end of the movement of slide chassis 1, main cam 53 further rotates, and the groove 60 for driving the loading lever depresses the cam pin 66. Thus loading lever 101 starts to move in the direction of the arrow A. Since loading arm depressed portion 109a is in contact with loading lever pin 111a and loading arm depressed portion 109b is in contact with loading lever pin 111b, loading arms 3a and 3b start to rotate in the directions of the arrows J and K around rotation shafts 5a and 5b, respectively, when loading lever 101 starts to move in the direction of the arrow A. FIG. 25 shows the state after the end of rotation of loading arms 3a and 3b. When loading arms 3a and 3b reach the state of FIG. 25, the operation of the guide roller (not shown) connected to the loading arms 3a and 3b to bring the magnetic tape (not shown) onto the drum 77 is completed.
As shown in FIG. 24, in the conventional magnetic recording reproducing apparatus, loading arms 3a, 3b are rotated by moving the loading lever 101 in the direction of the arrow A. Therefore, in the conventional recording reproducing apparatus, loading lever 101 as well as slide chassis 1 must be moved, which results in the complicated structure.